That is to say, they could decide to seed Williams anyway.
Following a tumultuous birth, when she needed emergency surgery after suffering a blood clot, just being back on the court is a remarkable achievement.
Williams, 36, lost to her sister Venus Williams in the last 32 of Indian Wells in March before being dumped by Naomi Osaka in Miami.
"After her pregnancy, Serena had to rebuild her body", Mouratoglou added.
Despite her lowly ranking she will be able to compete at Roland Garros under the WTA's protected ranking rule, which allows athletes returning from long absences to gain entry into tournaments using the ranking they had when they stopped playing.
"Can she do it?"
Serena Williams is without doubt the face of women's tennis as her achievements speak for herself. Williams "was not ready yet but needed to feel the competition, so she chose to play even though she was far from being at 100 percent", said Patrick Mouratoglou.
Serena Williams almost died while giving birth to her first child a year ago, and she subsequently has experienced difficulties returning to the WTA Tour following a 14-month layoff.
The former world number one has been snubbed of a seeding by French Open organisers, who chose to make their seedings based on WTA rankings.
Women's Final. d. Seles, a lefty who hit two-fisted forehands and backhands, won the 1990, 1991 and 1992 French Open titles.
The 25-year-old American's results on clay in the run-up to the French Open will hardly cause her opponents to shake in their boots but it is a sense of belonging as a reigning grand slam victor that could be what makes her most risky. "Everything is a lot looser, it takes time to get that back to where it once was. If you are suffering you know how to value it, how to enjoy it". "That's what it's going to take".
Yannick Noah remains the first, and so far, only Frenchman to win a singles title at Roland Garros.
"One can never count Serena out if she's in a draw", the American, who will be part of ITV's French Open coverage, said.
She is now ranked 453. "If she does reach the second week she will be hard to stop".
Serena Williams was recently spotted at the Royal Wedding of Prince Harry and Meghan Markle.
Fans and sponsors will be delighted to see Sharapova back on Court Philippe Chatrier, such is her pulling power.
It can only mean one thing - Maria Sharapova is about to play in a Grand Slam event.
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